In the 11th minute, Services midfielder Laramnieng Mawia broke through the defence and rolled the ball towards Jain P, who made no mistake and scored the goal to put his side ahead.
In the second half, Arjun Tudu came good in the 48th and 84th minute to help Services rout the opposition.
Assam have lost all the three matches played so far in the tournament.
Tomorrow, West Bengal and Punjab will play their next match here.